The invention relates to a hand-held transmitter for the wireless transmitting of signals for operating remote-controlled garage door installations or the like comprising a signal generating device, an energy source, and a hand-operable transmitter switch built into the transmitter housing.
Hand-held transmitters of this kind are known, and operate for example with an electric power supply in the form of a 9-volt battery, and allow a garage door, fitted with an appropriate receiver, to be opened or closed by means of electrical propulsion energy with the aid of a transmitted signal (for example, German Gebrauchsmusterschrift 76 26 730).
In particular, such hand-held transmitters should be made so small and handy that they can be carried around conveniently. It should be noted in this regard that modern electronics make it possible to build such transmitters in a very small space. In addition, the electrical power supply can be provided in relatively little space. On the other hand, the operating elements are of critical importance, especially the required hand-operable transmitter switch, for example, a pushbutton, which must not exceed certain dimensions because of the dimensions of the human hand.
It is often necessary to use at least two different receivers, one for each door of a two-door garage, or a driveway gate and a separate garage door. Different doors of this type should be openable selectively, in other words, the same signal should not open both doors. The reason for this may be that the owners may be different, or for safety reasons and the like.
From a consideration of space limitation it would be advantageous to provide a transmitter which emits two different signals, for example two electromagnetic signals of different frequencies. Since the two signals would not have to be transmitted simultaneously as a rule, the different transmitting frequencies could be easily obtained by modifying the oscillator circuit through changes in the circuit. The important point is that two different "on" states must be provided.
It would be possible to make these two different signal states capable of being selected with the aid of two switches, especially pushbutton switches. However, this would go against the desired effort to make the device small.
Thus, an object of the present invention is to provide a hand-held transmitter of the type described hereinabove, with the aid of which at least two different signal states can be set, without necessitating a corresponding number of switching devices accessible from the surface of the housing.
This object is achieved according to the present invention by providing in a hand-held transmitter for the wireless transmitting of signals for operating remote-controlled garage door installations or the like comprising a signal generating device, an energy source, and a hand-operable transmitter switch built into the transmitter housing, the improvement comprising means for selectively transmitting at least two different signals, said means including a switch which is position-dependent with respect to the force of gravity for selecting one of said at least two different signals to be transmitted.
The position-dependent switch provided according to the invention makes it possible to transmit at least two different signals with only one hand-operable transmitter switch such as a pushbutton. The position-dependent switch can be mounted at a fixed position nearly anywhere inside the housing, without affecting the shape of the housing, especially the outside, in any way. A single hand-operable transmitter switch such as a pushbutton accessible from the surface of the housing is sufficient, and can be provided at a convenient point so that the housing has the smallest possible dimensions.
The position-dependent switch can be a simple working contact or, in a preferred embodiment, a switching contact. In both cases, the switching states, associated with the different signals, are distinguished by virtue of the fact that the entire hand-held transmitter and the position-dependent switch mounted on the hand-held transmitter housing, assume two different positions in space with respect to gravity. These two positions are not critical, since only an unstable transition state must be provided. For example, a first transmitting position can be defined by virtue of the fact that the housing assumes an approximately horizontal position with its broad sides. In this position, the first transmitting frequency is emitted by pressing the pushbutton. On the other hand if the unit is raised to a vertical position, pushing on the same pushbutton will transmit the second frequency. However, when the unit is in a vertical position, for example, swiveling it through approximately 90.degree. through a certain perpendicular will differentiate between the two switching positions. There are many possiblities here, and no special details need be provided.
The position-dependent switch is characterized by a gravity-dependent switching element. In one preferred embodiment, the actual gravity-dependent switching element is a mercury filling which distinguishes between two different switching states as a function of gravity and the position of the hand-held transmitter in space. Such mercury switches are know of themselves, but with different designs, such that these switches are swivelably mounted on a fixed housing by means of electromagnetic forces or the like.
To operate a hand-held transmitter of the present invention, primary cells can be employed which have to be replaced after a certain period of operation. Secondary cells can also be used, which can be recharged with the aid of a charger. In any case, it is important for a certain minimum energy to be available to operate the transmitter. In order to display the functional readiness of the device and hence to detect any malfunctions in the condition of the power supply, according to the present invention, the unit is preferably provided with an optical power monitoring device. In one preferred embodiment, a light-emitting diode (LED) is used which, preferably when the pushbutton is actuated, shows whether the power supply still has enough energy in it.